Haven't worked with a Berger, but my buddy's .243 Win likes 46 gr of IMR-4350 under 80 gr RP PSPs & Win LRMs in PPU brass. The old brown book lists 48 gr as max w/ an 80 gr CNC and standard LR primers, so I'd expect it'd be in that neighborhood. My buddy's rifle started showing signs excessive presure at 47, but as I said this was w/ magnum primers.
Good luck,
efw
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